Identifying neurons for interoception using simultaneous profiling of activity- and projection- specific populations

项目摘要 内感受是身体感知自身内部状态的过程， 通过检测生理变化使身体能够适应变化的体内平衡 要求。内感受功能障碍可能导致对这些身体的错误预测错误。 需要，并越来越多地被认为是一些适应不良行为和精神疾病的基础。 疾病，包括成瘾和饮食失调。尽管如此， 识别内感受的潜在神经回路机制，因为非语言受试者（例如， 动物模型）不能自我报告内部状态。在这里，我们提出了一个新的概念行为 在动物模型中研究内感受的框架，以识别 编码内感受。此外，人类成像研究告诉我们，内感受依赖于 关键是大脑的一个研究不足的区域，岛叶皮层，但功能和相应的 来自岛叶皮质亚区（前向后）的投射尚未得到充分研究。 可以同时提供有关行为和预测的精确信息的方法， 因此需要高通量方法。分子谱分析技术已经越来越多地 用于识别可能作为基因与电路之间联系的细胞类型，但目前 技术有局限性，即剖析发生的方式。因此，我们也 我提出了一种新的转录组分子分析技术，称为SNAP-TRAP（同步 神经元活性和投射-翻译核糖体亲和纯化），这使得能够同时 活动依赖性和投射特异性神经元标记物的分析。我们会证实这一点 使用具有已知分子标记和行为标记的明确定义的神经回路的技术 后果然后，我们将应用的方法，岛叶皮层和它的作用，内感受。 这项技术也将使我们能够比较下一代RNA测序和单次测序。 细胞RNA测序，目的是鉴定用于行为验证的有用标记。最后我们 将把我们的发现映射到组织切片上，以获得空间转录组信息。通过 通过这些实验，我们希望获得一个全面的岛叶皮层转录组图谱， 可以根据特定的行为和预测来精确地描绘，并可以用作 了解内感受功能障碍如何导致适应不良行为的基础。SNAP- 然后，TRAP技术可能会被更广泛的神经科学界用于其他大脑区域， 行为任务，以深入了解复杂行为的神经基础及其 相关的精神疾病。

Project Summary Interoception, the process by which the body senses its own internal state, is critical to maintaining homeostasis through the detection of physiological changes that enable the body to adjust to changing demands. Dysfunction in interoception may lead to erroneous prediction errors concerning these bodily needs and is increasingly considered to underlie a number of maladaptive behaviors and psychiatric disorders, including addiction and eating disorders. Despite this, little progress has been made in identifying the underlying neural circuit mechanisms of interoception because non-verbal subjects (e.g. animal models) cannot self-report internal states. Here, we propose a novel conceptual behavioral framework for studying interoception in animal models in order to identify neuronal ensembles that encode interoception. Moreover, human imaging studies have informed us that interoception relies critically on an understudied area of the brain, the insular cortex, but the functions and corresponding projections from the insular cortex subregions (anterior to posterior) have not been well-studied. Methods that can simultaneously deliver precise information concerning behavior and projections in a high-throughput way are therefore required. Molecular profiling techniques have been increasingly useful for identifying cell types that might serves as the link between genes to circuits, but current techniques have limitations, namely the modality by which the profiling occurs. We therefore also propose a new transcriptomic molecular profiling technique, called SNAP-TRAP (Simultaneous Neuronal Activity and Projection – Translating Ribosome Affinity Purification), that enables coincident profiling of both activity-dependent and projection-specific neuronal markers. We will validate this technique using a well-defined neural circuit with known molecular markers and behavioral consequences. We will then apply the methodology to the insular cortex and its role in interoception. This technique will also enable us to make comparisons of next-generation RNA-sequencing to single- cell RNA sequencing for the purpose of identifying useful markers for behavioral validation. Lastly, we will map our findings back onto tissue sections to achieve spatial transcriptomic information. Through these experiments we hope to achieve a comprehensive transcriptomic map of the insular cortex that can be precisely delineated according to particular behaviors and projections, and can be used as a basis for understanding how dysfunction in interoception leads to maladaptive behaviors. The SNAP- TRAP technique may then be used by the broader neuroscience community in other brain regions and behavioral tasks to gain insights into the neural underpinnings of complex behaviors and their associated psychiatric disorders.